Project description:The acetylation levels of histones and other proteins change during aging and have been linked to neurodegeneration. Here we show that deletion of the histone acetyltransferase (HAT) co-factor Trrap specifically impairs the function of the transcription factor Sp1, reduces its stability and causes a decrease in histone acetylation at Sp1 target genes. Modulation of Sp1 function by Trrap acts as a hub regulating multiple processes involved in neuron and neural stem cells function and maintenance including microtubule dynamics and the Wnt signaling pathway. Consistently, Trrap conditional mutants exhibit all hallmarks of neurodegeneration including dendrite retraction and axonal swellings, neuron death, astrogliosis, microglia activation, demyelination and decreased adult neurogenesis. Our results uncovered a novel functional network, essential to prevent neurodegeneration, and involving the specific regulation of Sp1 transcription factor and its downstream targets by Trrap-HAT.
Project description:Neural crest cells are migratory progenitor cells that contribute to nearly all tissues and organs throughout the body. Their formation, migration and differentiation are regulated by a multitude of signaling pathways, that when disrupted can lead to disorders termed neurocristopathies. While work in avian and amphibian species has revealed essential factors governing the specification and induction of neural crest cells during gastrulation and neurulation in non-mammalian species, their functions do not appear to be conserved in mice, leaving major gaps in our understanding of neural crest cell formation in mammals. Here we describe Germ Cell Nuclear Factor (GCNF/Nr6a1), an orphan nuclear receptor, as a critical regulator of neural crest cell formation in mice. Gcnf null mutant mice, exhibit a major disruption of neural crest cell formation. The purpose of this experiment is to examine gene expression changes in response to Gcnf mutation in E9.0 mouse embryos.
Project description:The acetylation levels of histones and other proteins change during aging and have been linked to neurodegeneration. Here we show that deletion of the histone acetyltransferase (HAT) co-factor Trrap specifically impairs the function of the transcription factor Sp1, reduces its stability and causes a decrease in histone acetylation at Sp1 target genes. Modulation of Sp1 function by Trrap acts as a hub regulating multiple processes involved in neuron and neural stem cells function and maintenance including microtubule dynamics and the Wnt signaling pathway. Consistently, Trrap conditional mutants exhibit all hallmarks of neurodegeneration including dendrite retraction and axonal swellings, neuron death, astrogliosis, microglia activation, demyelination and decreased adult neurogenesis. Our results uncovered a novel functional network, essential to prevent neurodegeneration, and involving the specific regulation of Sp1 transcription factor and its downstream targets by Trrap-HAT.